Able to change vnic type on a bound port

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/neutron/+/892815

As I wrote on the review it can be something to discuss, but currently PUT is allowed on the API:

https://opendev.org/openstack/neutron-lib/src/branch/master/neutron_lib/api/definitions/portbindings_extended.py#L87

https://opendev.org/openstack/neutron-lib/src/branch/master/neutron_lib/api/definitions/portbindings.py#L187

so I would add a doc entry (perhaps to the api-ref at least) that PUT works only for UNBOUND ports

Related fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/neutron-lib/+/900826

Reviewed: https://review.opendev.org/c/openstack/neutron/+/892815
Committed: https://opendev.org/openstack/neutron/commit/354205a42372ce2480b14a5e9b80eb0d91991b37
Submitter: "Zuul (22348)"
Branch: master

commit 354205a42372ce2480b14a5e9b80eb0d91991b37
Author: Jakub Libosvar <email address hidden>
Date: Fri Aug 25 01:52:24 2023 +0000

    Forbid updating vnic type on a bound port

    The vnic type should not be changed once the port is bound since it's
    related to the actual port binding. The patch validates the port update
    operation and fails the update if the vnic type is attempted to be
    changed on a bound port.

    Closes-bug: #2033090
    Change-Id: I5cb79d9da96ba41a7787083c81f522c328fae049
    Signed-off-by: Jakub Libosvar <email address hidden>

Reviewed: https://review.opendev.org/c/openstack/neutron-lib/+/900826
Committed: https://opendev.org/openstack/neutron-lib/commit/b99cfa600419a2252b7a6d6476e6a07fe8ad429b
Submitter: "Zuul (22348)"
Branch: master

commit b99cfa600419a2252b7a6d6476e6a07fe8ad429b
Author: Jakub Libosvar <email address hidden>
Date: Mon Nov 13 21:50:37 2023 +0000

    api-ref: Document only unbound ports vnic_type updates

    The Neutron patch linked below changes behavior of API update requests
    to vnic_type port binding attribute on bound ports. It's no longer
    allowed to update the vnic_type if the port is already bound.

    Depends-On: https://review.opendev.org/c/openstack/neutron/+/892815
    Related-bug: #2033090
    Change-Id: Ic5c6d54a1e5e57e977623ac6a4e2e6278f7237b7
    Signed-off-by: Jakub Libosvar <email address hidden>

This issue was fixed in the openstack/neutron 24.0.0.0b1 development milestone.